Public Class TestForm
    Dim Test As New TestClass

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        PropertyGrid1.SelectedObject = Test
    End Sub

    Private Sub MenuItem1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MenuItem1.Click
        Test.ShowIt()
    End Sub
End Class
                                                                                                                                                                                                                                                                                                                                                                                                       